1. Field of the Invention
The present invention relates to a phosphate compound, and in particular relates to an organic silicon phosphate and fabrication method thereof.
2. Description of the Related Art
There are two kinds of flame retardants: inorganic and organic types. Compared with organic type flame retardant, higher amounts of the inorganic flame retardants must be added to the resin. However, when the addition of inorganic flame retardants is too high, the physical properties of resin deteriorate. Organic flame retardants come in two types; halogen and phosphorus. However, because the halogen-type flame retardants emit toxic gas and smog during fire, many efforts have been devoted towards developing the phosphorous type flame retardants.
The flame retardant effect of the phosphorus type depends on the amount of phosphorous content. Further, the mixing of flame retardants and resin using a heat-press process requires high temperature. Therefore, there is a need to develop a phosphorous type flame retardant having high phosphorous content and high thermal stability.
Monomer-types of phosphorous flame retardant, such as triphenyl phosphate (TPP) or tricresyl phosphate (TCP) was initially developed. However, because the major components of the monomer-type phosphorus flame retardant has a low molecular weight, it easily evaporates and causes environmental pollution. As a result, condensed phosphoric ester has been developed. Referring to U.S. Pat. Nos. 6,319,432, 6,605,736, 6,605,737 and 6613928, these patents disclose the fabrication methods of the condensed phosphoric ester, wherein the amounts of the low molecular compounds, which easily evaporate, are reduced.
Organic silane material retains the advantages of both the organic and the inorganic material. It is resistant to high and low temperature, it has excellent electrical insulating properties, high chemical stability and good durable properties. JP patent 2000-256378 disclose a phosphate containing silicon having good flame retardant properties and high thermal stability.
Accordingly, there is a need to develop an organic silicon phosphate which not only have the advantages of the organic silicon but also has high phosphorous content and high thermal stability.